title: Stroke after cardiac surgery and its association with asymptomatic carotid disease: an updated systematic review and meta-analysis.
abstract: OBJECTIVE
  (i) Prevalence of stroke in neurologically symptomatic/asymptomatic patients with unilateral/bilateral carotid disease (including occlusion) undergoing cardiac surgery without prophylactic carotid endarterectomy (CEA) or carotid stenting (CAS). (ii) Prevalence of stroke in asymptomatic patients with unilateral/bilateral carotid disease (excluding occlusion) who underwent isolated cardiac surgery. (iii) Prevalence of stroke in the hemisphere ipsilateral to a non-operated asymptomatic stenosis in patients with severe bilateral carotid disease undergoing a synchronous unilateral CEA + cardiac procedure.
  
  
  METHODS
  Systematic Review and meta-analysis.
  
  
  RESULTS
  Cardiac surgery patients with a symptomatic/asymptomatic 50-99% stenosis or occlusion incurred a 7.4% stroke risk (95%CI 4.8-9.9), increasing to 9.1% (95%CI 4.8-16) in those with 80-99% stenoses or occlusion. After excluding patients with a history of stroke/TIA and those with isolated/bilateral occlusions, the stroke risk fell to 3.8% (95%CI 2.0-4.8) in patients with asymptomatic 50-99% stenoses and 2.0% in those with 70-99% stenoses (95%CI 1.0-5.7). The prevalence of ipsilateral stroke in patients with a unilateral, asymptomatic 50-99% stenosis was 2.0% (1.0-3.8), while the risk of any stroke was only 2.9% (2%-5.7%). These risks did not increase with stenosis severity (70-99%, 80-99%). Patients with bilateral, asymptomatic 50-99% stenoses or a 50-99% stenosis + contralateral occlusion incurred a 6.5% stroke risk following cardiac surgery, while the risk of death/stroke was 9.1% (3.8%-20.6%). Patients with bilateral 80-99% stenoses undergoing a unilateral synchronous cardiac/carotid revascularisation incurred a 5.7% risk of stroke in the hemisphere ipsilateral to the non-operated, contralateral stenosis.
  
  
  CONCLUSIONS
  There is no compelling evidence supporting a role for prophylactic CEA/CAS in cardiac surgery patients with unilateral asymptomatic carotid disease. Prophylactic CEA/CAS might still be considered in patients with severe, bilateral asymptomatic carotid disease, but such a strategy would only benefit 1-2% of all cardiac surgery patients.
authors.affiliation: The Department of Vascular Surgery at Leicester Royal Infirmary, Leicester LE2 7LX, UK. ross.naylor@uhl-tr.nhs.uk
authors.forename: A R
authors.initials: AR
authors.lastname: Naylor
authors.forename: M J
authors.initials: MJ
authors.lastname: Bown
mesh_terms: D006348:Cardiac Surgical Procedures / Q000009:adverse effects*; D002340:Carotid Artery Diseases / Q000150:complications*; D014943:Global Health; D006331:Heart Diseases / Q000150:complications* / Q000601:surgery; D006801:Humans; D015995:Prevalence; D020521:Stroke / Q000453:epidemiology* / Q000209:etiology